— —, or natural walls, of Rowan, N. C., xiv, 242.

— —, in Montgomery, Vt., xxii, 189.

— —, connection of, with the iron ores of Essex Co., N. Y., E. Emmons, xl, 81.

— —, effect on limestone, xxix, 351.

— —, action on mica slate, xxvii, 343.

— of porphyry in Nova Scotia, xv, 203, 213.

Dilatation of gases, V. Regnault, xliv, 63.

Diluvial action, in Sullivan Co., N. Y., facts relating to, W. A. Thompson, xxiii, 243.

— scratches, see [Scratches.]

Dimorphism, viii, 378; xlvi, 370.